Systems and Methods for Deploying Spacecraft

ABSTRACT

In an example, a spacecraft system includes a plurality of spacecraft in a stack. The stack has one or more layers, each layer includes at least two spacecraft, and each spacecraft is releasably coupled to one or more adjacent spacecraft in the stack. The spacecraft system also includes a controller configured to, for each layer, (i) cause the layer to release from the stack, and (ii) after the layer releases from the stack, cause the at least two spacecraft in the layer to release from each other.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/373,166, filed on Dec. 8, 2016, the contents of which is herebyincorporated by reference in its entirety.

FIELD

The present disclosure generally relates to spacecraft systems andmethods, and more particularly to, systems and methods for deployingmultiple spacecraft from a launch vehicle.

BACKGROUND

Unless otherwise indicated herein, the materials described in thissection are not prior art to the claims and are not admitted to be priorart by inclusion in this section.

To reduce launch costs, many launch vehicles used to carry a payloadinto outer space have been designed to simultaneously carry a pluralityof spacecraft such as, for example, satellites. In one approach, thelaunch vehicle includes a dedicated dispenser system, which separatelysupports each spacecraft during lift-off and then individually dispenseseach spacecraft in orbit. One drawback is that the dispenser systemtends to be relatively bulky and heavy, which reduces the useablepayload that can be carried into orbit by the launch vehicle.

SUMMARY

A method and system for deploying spacecraft from a launch vehicle isdisclosed. In an example, a spacecraft system includes a plurality ofspacecraft in a stack. The stack has one or more layers, each layerincludes at least two spacecraft, and each spacecraft is releasablycoupled to one or more adjacent spacecraft in the stack. The spacecraftsystem also includes a controller configured to, for each layer, (i)cause the layer to release from the stack, and (ii) after the layerreleases from the stack, cause the at least two spacecraft in the layerto release from each other

In another example, a method of deploying a plurality of spacecraft froma launch vehicle is disclosed. The plurality of spacecraft are in astack having one or more layers, each layer includes at least twospacecraft, and each spacecraft is releasably coupled to one or moreadjacent spacecraft in the stack. The method includes (i) releasing,layer by layer, the one or more layers from the stack, and (ii) for eachlayer, after releasing the layer from the stack, releasing the at leasttwo spacecraft of the layer from each other.

In another example, disclosed is a non-transitory computer-readablemedium having stored thereon, program instructions that when executed bya controller, causes a spacecraft system to perform a set of acts. Thespacecraft system includes a plurality of spacecraft in a stack, thestack has one or more layers, each layer includes at least twospacecraft, and each spacecraft is releasably coupled to one or moreadjacent spacecraft in the stack. The set of acts include (i) releasing,layer by layer, the one or more layers from the stack, and (ii) for eachlayer, after releasing the layer from the stack, releasing the at leasttwo spacecraft of the layer from each other.

These as well as other aspects, advantages, and alternatives will becomeapparent to those of ordinary skill in the art by reading the followingdetailed description with reference where appropriate to theaccompanying drawings. Further, it should be understood that thedescription provided in this summary section and elsewhere in thisdocument is intended to illustrate the claimed subject matter by way ofexample and not by way of limitation.

BRIEF DESCRIPTION OF THE FIGURES

The novel features believed characteristic of the illustrativeembodiments are set forth in the appended claims. The illustrativeembodiments, however, as well as a preferred mode of use, furtherobjectives and descriptions thereof, will best be understood byreference to the following detailed description of an illustrativeembodiment of the present disclosure when read in conjunction with theaccompanying drawings.

FIG. 1 depicts a simplified diagram of a rocket according to an exampleembodiment.

FIG. 2 depicts a simplified block diagram of a spacecraft systemaccording to an example embodiment.

FIG. 3 depicts a perspective view of a spacecraft system according to anexample embodiment.

FIG. 4A depicts a perspective view of a spacecraft according to anexample embodiment.

FIG. 4B depicts another perspective view of the spacecraft shown in FIG.4A.

FIG. 5 depicts a perspective view of an adaptor according to an exampleembodiment.

FIGS. 6A-6H depict a spacecraft system deploying spacecraft according toan example embodiment.

FIG. 7 depicts a flow chart of an example process for deployingspacecraft, according to an example embodiment.

FIG. 8 depicts a flow chart of an example process for deployingspacecraft, according to an example embodiment.

FIG. 9 depicts a flow chart of an example process for deployingspacecraft, according to an example embodiment.

FIG. 10 depicts a flow chart of an example process for deployingspacecraft, according to an example embodiment.

FIG. 11 depicts a flow chart of an example process for deployingspacecraft, according to an example embodiment.

FIG. 12 depicts a flow chart of an example process for deployingspacecraft, according to an example embodiment.

DETAILED DESCRIPTION

I. Overview

The methods and systems of the present disclosure provide spacecraftsystems and methods for deploying multiple spacecraft from a launchvehicle. The spacecraft can be, for example, satellites and/orinterplanetary probes. As an example, the launch vehicle can be a rocketfor carrying a payload from a planetary surface into outer space.

Within examples, a spacecraft system includes a plurality of spacecraftarranged in a stack. The stack has one or more layers and each layer hasat least two spacecraft. Each of the spacecraft in the stack isreleasably coupled to one or more adjacent spacecraft, which can be inthe same layer as the spacecraft, an adjacent layer immediately abovethe spacecraft, and/or an adjacent layer immediately below thespacecraft.

The spacecraft system can further include an adaptor that couples thestack of spacecraft to a launch vehicle. The adaptor can have a firstend releasably coupled to a bottom-most layer of the stack and a secondend configured to couple to a support surface of the launch vehicle. Insome instances, the support surface of one type of launch vehicle maydiffer from the support surface of another type of launch vehicle. Toadapt the spacecraft system to a variety of different launch vehicles, aset of adaptors can be provided with a plurality of second endconfigurations, which respectively correspond to the support surfaces ofdifferent types of launch vehicles. As such, the spacecraft system canbe readily deployed in a variety of different types of launch vehiclesby selecting, from among the set of adaptors, an adaptor correspondingto a particular type of launch vehicle to be used for a particularlaunch of the spacecraft system.

The spacecraft system can include a plurality of releasable fastenersthat releasably couple the spacecraft to the adjacent spacecraft and/orthe adaptor. In general, each releasable fastener is actuatable toprovide a mechanical release of respective components coupled to oneanother by the releasable fastener. For example, each releasablefastener can couple respective components of the spacecraft system toeach other in a first state of the releasable fastener and release therespective components from each other in a second state of thereleasable fastener. Each releasable fastener can be selectivelyactuated between the first state and the second state responsive to asignal received from a controller.

In one aspect, the controller can transmit signals to the releasablefasteners to thereby cause the layers of spacecraft to release, layer bylayer, from the stack. For each layer, after the layer releases from thestack, the controller can transmit further signals to cause thespacecraft in the layer to release from each other. In one example, thecontroller causes the layers to release from the stack, layer by layer,in an order from a top-most layer of the stack to the bottom-most layerof the stack. In another example, if a fault is detected, the controllercan cause the stack to release from the adaptor and then cause thelayers to release, layer by layer, in an order from the bottom-mostlayer to the top-most layer. By the term “top-most layer,” it is meantthe layer in the stack that is farthest from the launch vehicle. By theterm “bottom-most layer,” it is meant the layer in the stack that isclosest to the launch vehicle.

The spacecraft system can further include a plurality of biasingdevices, which can facilitate separating the layers from the stackand/or the spacecraft from each other responsive to the controllerreleasing the layers from the stack and/or the spacecraft from eachother. By applying biasing forces to facilitate separating the layersand/or spacecraft from each other, the risk of collisions between thespacecraft can be reduced or minimized. Additionally, using biasingdevices to apply biasing forces can provide for passive separation ofthe spacecraft, which can help to conserve fuel for thrusters that maybe used for other purposes during operation of the spacecraft (e.g., tomaintain the spacecraft in an assigned orbital slot).

In an example, the biasing devices can cause each layer to rotate as thelayer separates from the stack. For instance, for each layer of thestack, at least one of the biasing devices can apply a different biasingforce to the layer than at least another of the biasing devices to causethe layer to rotate as the layer separates from the stack. In animplementation, the layer can rotate about an axis normal to a directionof the sun. By rotating the layer about an axis normal to the directionof the sun, the spacecraft of the layer can be more equally exposed tothe sun during each rotation. This can facilitate providing a thermallyand power stable configuration of the spacecraft in the layer duringseparation from the stack.

The spacecraft system of the present disclosure provides a number ofadvantages over conventional spacecraft dispensing systems. For example,because the spacecraft are releasably coupled to each other in a stack,the spacecraft system can omit a bulky and heavy structure ofconventional dispenser systems. As such, the spacecraft system of thepresent disclosure can deploy spacecraft in greater quantities, sizes,and/or weights per launch than conventional dispenser systems for agiven launch vehicle.

II. Example Systems

FIG. 1 depicts a rocket 110 including a spacecraft system 112 accordingan example of the disclosure. As shown in FIG. 1, the rocket 110includes a fairing 114 coupled to a launch vehicle 116. The launchvehicle 116 provides a rocket engine for propelling the rocket 110during launch and/or flight. For example, the launch vehicle 116 caninclude one or more internal fuel chambers containing a rocket fuel(i.e., a propellant), combustion chambers, and/or rocket engine nozzles118. The combustion chamber can combust the rocket fuel to produce ahot, high pressure gas, which the rocket engine nozzle 118 exhausts awayfrom the launch vehicle 116. The rocket engine nozzle 118 can acceleratethe gas received from the combustion chamber to facilitate convertingthermal energy of the gas into kinetic energy of the launch vehicle 116.Within examples, the launch vehicle 116 can include a single enginestage or a plurality of engine stages, which separate and ignite insequence.

The fairing 114 is coupled to the launch vehicle 116 and encloses thespacecraft system 112 to protect the spacecraft system 112 fromaerodynamic forces during flight through an atmosphere. The fairing 114can then separate from the launch vehicle 116 after the aerodynamicforces drop below a certain value and/or the launch vehicle 116 reachesa particular location. By separating the fairing 114 from the launchvehicle 116, the spacecraft system 112 can be exposed to an externalenvironment such as, for example, outer space. The spacecraft system 112can then deploy into orbit a plurality of spacecraft such as, forexample, satellites and/or interplanetary probes, as described below.

FIG. 2 depicts a simplified diagram of the spacecraft system 112according to an example of the disclosure. As shown in FIG. 2, thespacecraft system 112 includes a plurality of spacecraft 120A-120Farranged in a stack 122, which has a plurality of layers 124A-124C withat least two spacecraft 120A-120F per layer 124A-124C. Moreparticularly, the spacecraft system 112 includes a first layer 124Ahaving a first spacecraft 120A and a second spacecraft 120B, a secondlayer 124B having a third spacecraft 120C and a fourth spacecraft 120D,and a third layer 124C having a fifth spacecraft 120E and a sixthspacecraft 120F. The first layer 124A is a top-most layer of the stack122 and the third layer 124C is a bottom-most layer of the stack 122. Asshown in FIG. 2, the third layer 124C is releasably coupled to a firstend 128 of an adaptor 126. A second end 130 of the adaptor 126 isconfigured to couple to the launch vehicle 116.

Although the spacecraft system 112 includes three layers 124A-124C inthe example depicted by FIG. 2, the spacecraft system 112 can include agreater quantity of layers 124A-124C or a fewer quantity of layers124A-124C in another example. Hence, the quantity of layers 124A-124Cmay be more than three or as few as one (e.g., layer 124C) such thatrelease from the adaptor 126 may be accomplished as herein shown anddescribed. Similarly, although the spacecraft system 112 includes twospacecraft 120A-120F per layer 124A-124C in the example depicted by FIG.2, the spacecraft system 112 can include more than two spacecraft120A-120F per layer 124A-124C in another example. Within examples, thespacecraft system 112 can include an even quantity or an odd quantity ofspacecraft 120A-120F per layer 124A-124C.

Further, while multiple spacecraft 120A-120F are shown in each layer124A-124C, it is not necessary that each spacecraft 120A-120F beidentical with or arranged symmetrically with other spacecraft 120A-120Fin the same layer 124A-124C. Rather, in some examples, it is onlynecessary that the assembled spacecraft 120A-120F in the particularlayer 124A-124C have substantially the same height and fit within thecontours of the fairing 114 to ensure the stability of each layer124A-124C. In this manner, spacecraft 120A-120F of different sizes andvolumes may be grouped together in a layer 124A-124C having a uniformheight. Further, in this manner, a plurality of spacecraft 120A-120F maybe arranged in a stack 122, wherein the stack 122 has one or more layers124A-124C and each layer 124A-124C includes at least two spacecraft120A-120F. Each spacecraft 120A-120F in a layer 124A-124C may bereleasably coupled vertically to one or more adjacent spacecraft120A-120F in the stack 122 as well as horizontally in a layer 124A-124C.The terms vertical and horizontal are relative terms and not intended toconvey an absolute orientation.

Additionally, within examples, the quantity of layers 124A-124C and/orthe quantity of spacecraft 120A-120F per layer 124A-124C can bedetermined based on at least one factor selected from a group of factorsincluding the type of launch vehicle 116 used to transport thespacecraft system 112, the type of spacecraft 120A-120F to be deployed,a total spacecraft constellation size, a quantity of spacecraft perorbit plane and/or altitude, a spacecraft constellation design life andreplenishment plan, collision on launch assessment (COLA) requirements,a spacecraft constellation orbit phasing, and/or constellationcrosslink, a final orbital altitude of the spacecraft 120A-120F, a massof each individual spacecraft 120A-120F, and/or a capability of theselected launch vehicle 116.

Each spacecraft 120A-120F is releasably coupled to one or more adjacentspacecraft 120A-120F in the stack 122 and/or the adaptor 126. Forexample, in FIG. 2, the first spacecraft 120A is releasably coupled tothe second spacecraft 120B and the third spacecraft 120C. The secondspacecraft 120B is releasably coupled to the first spacecraft 120A andthe fourth spacecraft 120D. The third spacecraft 120C is releasablycoupled to the first spacecraft 120A, the fourth spacecraft 120D, andthe fifth spacecraft 120E. The fourth spacecraft 120D is releasablycoupled to the second spacecraft 120B, the third spacecraft 120C, andthe sixth spacecraft 120F. The fifth spacecraft 120E is releasablycoupled to the third spacecraft 120C, the sixth spacecraft 120F, and theadaptor 126. The sixth spacecraft 120F is releasably coupled to thefourth spacecraft 120D, the fifth spacecraft 120E, and the adaptor 126.

To releasably couple the spacecraft 120A-120F to each other and/or theadaptor 126 as described above, the spacecraft system 112 includes aplurality of releasable fasteners 134A-1341. In general, each releasablefastener 134A-1341 is actuatable to provide a mechanical release ofrespective components (i.e., spacecraft 120A-1201 and/or adaptor 126)coupled to one another by the releasable fastener 134A-1341. Forexample, each releasable fastener 134A-1341 can couple respectivecomponents of the spacecraft system 112 to each other in a first stateand release the respective components from each other in a second state.The releasable fastener 134A-1341 can be selectively actuated betweenthe first state and the second state responsive to a signal receivedfrom a controller 136 (e.g., via wired and/or wireless communication).

The controller 136 can be implemented using hardware, software, and/orfirmware. For example, controller 136 can include one or more processorsand a non-transitory computer readable medium (e.g., volatile and/ornon-volatile memory) that stores machine language instructions or otherexecutable instructions. The instructions, when executed by the one ormore processors, may cause controller 136 to carry out the variousoperations of the spacecraft system 112 described herein. Withinexamples, the controller 136 can be on the rocket 110 and/or at a groundcontrol station.

In FIG. 2, the plurality of releasable fasteners 134A-1341 include oneor more first releasable fastener(s) 134A that releasably couple thefirst spacecraft 120A and the second spacecraft 120B, one or more secondreleasable fastener(s) 134B that releasably couple the first spacecraft120A and the third spacecraft 120C, one or more third releasablefastener(s) 134C that releasably couple the second spacecraft 120B andthe fourth spacecraft 120D, one or more fourth releasable fastener(s)134D that releasably couples the third spacecraft 120C and the fourthspacecraft 120D, one or more fifth releasable fastener(s) 134E thatreleasably couple the third spacecraft 120C and the fifth spacecraft120E, one or more sixth releasable fastener(s) 134F that releasablycouple the fourth spacecraft 120D and the sixth spacecraft 120F, one ormore seventh releasable fastener(s) 134G that releasably couple thefifth spacecraft 120E and the sixth spacecraft 120F, one or more eighthreleasable fastener(s) 134H that releasably couple the fifth spacecraft120E and the adaptor 126, and one or more ninth releasable fastener(s)1341 that releasably couple the sixth spacecraft 120F and the adaptor126.

As examples, the releasable fasteners 134A-1341 can include marmanbands, separation nuts, frangible nuts, separation bolts, bolt cutters,wire cutters, cable cutters, split spool devices (e.g., fusible wiresand/or shaped-memory alloy wires), solenoid actuated nuts, pin pushers,and/or pin pullers. As further examples, in some implementations, eachreleasable fastener 134A-1341 can include a pyrotechnic charge that canbe activated remotely by the controller 136 to cause the pyrotechniccharge to break the releasable fastener 134A-1341 into pieces andthereby release the components coupled by the releasable fastener134A-1341. In other implementations, the releasable fastener 134A-1341can include a non-explosive actuator that can be activated remotely bythe controller 136. The type of releasable fasteners 134A-1341 used inthe spacecraft system 112 can be determined based on one or more factorsincluding, for example, susceptibility to electromagnetic interference,release response time, release shock, capability to withstand launchloads, capability to sustain preloads, power input to actuate, weight,size, temperature sensitivity, and/or release reliability.

As noted above, the controller 136 can transmit signals to selectivelyactuate one or more releasable fasteners 134A-1341 at a time. Accordingto an aspect of the disclosure, the controller 136 is configured tocause the layers 124A-124C of spacecraft 120A-120F to release, layer bylayer, from the stack 122 and the adaptor 126. In one example, thecontroller 136 is configured to cause the layers 124A-124C to release inan order from the top-most layer 124A in the stack 122 to thebottom-most layer 124C in the stack 122. For instance, the controller136 can transmit a first signal to actuate the second releasablefastener(s) 134B and the third releasable fastener(s) 134C and therebycause the first layer 124A to release from the stack 122. The controller136 can then transmit a second signal to actuate the fifth releasablefastener(s) 134E and the sixth releasable fastener(s) 134F and therebyrelease the second layer 124B from the stack 122. The controller 136 canfurther transmit a third signal to actuate the eighth releasablefastener(s) 134H and the ninth releasable fastener(s) 1341 to releasethe third layer 124C from the adaptor 126.

When each layer 124A-124C releases from the stack 122 and/or the adaptor126, the spacecraft 120A-120F within the layer 124A-124C are coupled toeach other. For each layer 124A-124C, the controller 136 can transmit anadditional signal to cause the spacecraft 120A-120F in the layer124A-124C to release from each other after the layer 124A-124C releasesfrom the stack 122 and/or the adaptor 126. For example, after the firstlayer 124A releases from the stack 122, the controller 136 can transmita signal to actuate the first releasable fastener(s) 134A and therebycause the first spacecraft 120A and the second spacecraft 120B torelease from each other. Similarly, after the second layer 124B releasesfrom the stack 122, the controller 136 can transmit a signal to actuatethe fourth releasable fastener(s) 134D and thereby cause the thirdspacecraft 120C and the fourth spacecraft 120D to release from eachother. After the third layer 124C releases from the adaptor 126, thecontroller 136 can transmit a signal to actuate the seventh releasablefastener(s) 134G and thereby cause the fifth spacecraft 120E and thesixth spacecraft 120F to release from each other.

As also shown in FIG. 2, the spacecraft system 112 can include aplurality of biasing devices 138A-1381 between respective components ofthe spacecraft system 112 such as, for instance, between adjacentspacecraft 120A-120F and/or between the spacecraft 120E-120F of thebottom-most layer 124C and the adaptor 126. The biasing devices138A-1381 apply biasing forces between the respective components of thespacecraft system 112 to urge the respective components away from eachother. As such, while the releasable fasteners 134A-1341 couple therespective components in the first state, the biasing forces applied bythe biasing devices 138A-1381 preload the releasable fasteners134A-1341. Then, responsive to the controller 136 actuating thereleasable fasteners 134A-1341 from the first state to the second state,the biasing forces applied to the respective components by the biasingdevices 138A-1381 cause the components to separate from each other.

In FIG. 2, the biasing devices 138A-1381 include a first set ofinterlayer biasing devices 138A-138F and a second set of intralayerbiasing devices 138G-1381. The first set of interlayer biasing devices138A-138F are between the adjacent layers 124A-124C of the stack 122,and between the bottom-most layer 124C and the adaptor 126. For example,in FIG. 2, the first set of interlayer biasing devices 138A-138F includeone or more first biasing device(s) 138A between the first spacecraft120A and the third spacecraft 120C, one or more second biasing device(s)138B between the second spacecraft 120B and the fourth spacecraft 120D,one or more third biasing devices(s) 138C between the third spacecraft120C and the fifth spacecraft 120E, one or more fourth biasing device(s)138D between the fourth spacecraft 120D and the sixth spacecraft 120F,one or more fifth biasing device(s) 138E between the fifth spacecraft120E and the adaptor 126, and one or more sixth biasing device(s) 138Fbetween the sixth spacecraft 120F and the adaptor 126. The first set ofinterlayer biasing devices 138A-138F can thus apply biasing forces tothe layers 124A-124C to facilitate separating each layer 124A-124C fromthe stack 122 after the layer 124A-124C releases from the stack 122.

In an implementation, the first set of interlayer biasing devices138A-138F are configured to cause each layer 124A-124C to rotate as thelayer 124A-124C separates from the stack 122 and/or the adaptor 126. Forexample, for each layer 124A-124C of the stack 122, at least one of thebiasing devices 138A-138F can apply a different biasing force to thelayer 124A-124C than at least another of the biasing devices 138A-138Fsuch that the layer 124A-124C rotates as the layer 124A-124C separatesfrom the stack 122.

In FIG. 2, for instance, the first biasing device(s) 138A can apply adifferent biasing force to the first layer 124A than the third biasingdevice(s) 138C to cause the first layer 124A to rotate as the firstlayer 124A separates from the stack 122. Additionally, the third biasingdevice(s) 138C can apply a different biasing force to the second layer124B than the fourth biasing device(s) 138D to cause the second layer124B to rotate as the second layer 124B separates from the stack 122.Similarly, the fifth biasing device(s) 138E can apply a differentbiasing force to the third layer 124C than the sixth biasing device(s)138F to cause the third layer 124C to rotate as the third layer 124Cseparates from the adaptor 126.

In one example, the plurality of biasing devices 138A-1381 can include aplurality of springs. For each layer 124A-124C of the stack 122, atleast one of the springs can have a different characteristic than atleast another of the springs such that the layer 124A-124C rotates asthe layer 124A-124C separates from the stack 122. For instance, at leastone of the springs can have a different spring constant than the atleast another of the springs, and/or at least one of the springs canhave a different length than at least another of the springs. In afurther example, the springs can be provided in different quantitiesand/or locations with respect to the layer 124A-124C to cause the layer124A-124C to rotate as the layer 124A-124C separates from the stack 122.

The second set of the intralayer biasing devices 138G-1381 are betweenadjacent spacecraft 120A-120F within the same layer 124A-124C as eachother. For example, in FIG. 2, the second set of intralayer biasingdevices 138G-131 include one or more seventh biasing device(s) 138Gbetween the first spacecraft 120A and the second spacecraft 120B in thefirst layer 124A, one or more eighth biasing device(s) 138H between thethird spacecraft 120C and the fourth spacecraft 120D in the second layer124B, and one or more ninth biasing device(s) 1381 between the fifthspacecraft 120E and the sixth spacecraft 120F in the third layer 124C.The second set of intralayer biasing devices 138G-1381 can thus applybiasing forces between the adjacent spacecraft 120A-120F to facilitateseparating the adjacent spacecraft 120A-120F from each other after (i)the layer 124A-124C containing the adjacent spacecraft 120A-120Freleases and separates from the stack 122, and (ii) the adjacentspacecraft 120A-120F in the layer 124A-124C release from each other.

FIG. 3 is a perspective view of the spacecraft system 112 according toan example. As shown in FIG. 3, the spacecraft system 112 includes theplurality of spacecraft 120A-120F arranged in the stack 122, the stack122 has the plurality of layers 124A-124C, and each layer 124A-124C hasat least two of the spacecraft 120A-120F. Additionally, in FIG. 3, eachof the spacecraft 120A-120F is releasably coupled to one or moreadjacent spacecraft 120A-120F, and the adaptor 126 is releasably coupledto the bottom-most layer 124C of the stack 122 as described above withrespect to FIG. 2.

In the example shown in FIG. 3, the adjacent spacecraft 120A-120F and/orthe adaptor 126 are coupled to each other by a plurality of releasablefasteners (e.g. releasable fastening devices) in the form of separationnuts 234; however, additional or alternative releasable fasteners can beused in other examples. Accordingly, as described above, the separationnuts 234 (i) couple the adjacent spacecraft 120A-120F and/or the adaptor126 to each other in the first state and (ii) release the adjacentspacecraft 120A-120F and/or the adaptor 126 from each other in thesecond state. Also, as described above, the separation nuts 234 areactuatable between the first state and the second state responsive tosignals received from the controller 136. The timing of the simultaneousor nearly simultaneous release of each of the plurality of separationnuts 234 is not critical as long as the described separation process isnot substantially affected.

To further illustrate the separation nuts 234, FIG. 4A depicts a frontperspective view and FIG. 4B depicts a rear perspective view of thethird spacecraft 120C according to an example. As shown in FIGS. 4A-4B,the third spacecraft 120C includes a plurality of top separation nuts234A on a top surface 140 of the spacecraft 120C, a plurality of bottomseparation nuts 234B on a bottom surface 142 of the spacecraft 120C, anda plurality of lateral separation nuts 234C on a lateral surface 144 ofthe spacecraft 120C. The top separation nuts 234A are configured toreleasably couple the spacecraft 120C to the adjacent spacecraft 120A inthe layer 124A above the spacecraft 120C. The bottom separation nuts234B are configured to releasably couple the spacecraft 120D to theadjacent spacecraft 120E in the layer 124C below the spacecraft 120C.The lateral separation nuts 234C are configured to releasably couple thespacecraft 120C to the adjacent spacecraft 120D in the same layer 124Bas the spacecraft 120C.

Although the separation nuts 234A-234C are located at peripheral cornersof the top surface 140, the bottom surface 142, and the lateral surface144 in FIGS. 4A-4B, the separation nuts 234A-234C can be at differentlocations on the top surface 140, the bottom surface 142, and/or thelateral surface 144 in another example. Additionally, in anotherexample, the top surface 140, the bottom surface 142, and/or the lateralsurface 144 can include a greater or lesser quantity of separation nuts234A-234C than the quantities of separation nuts 234A-234C depicted inFIGS. 4A-4B.

Referring back to FIG. 3, the first end 128 of the adaptor 126 iscoupled to the bottom-most layer 124C of the stack 122 and the secondend 130 of the adaptor 126 is configured to couple to a support surface132 (shown in FIG. 1) of the launch vehicle 116. FIG. 5 depicts aperspective view of the adaptor 126 according to an example of thedisclosure. As shown in FIG. 5, the first end 128 can be configuredaccording to a configuration of the bottom-most layer 124C. For example,the first end 128 can include a plurality of separation nuts 234 thatcouple with corresponding structures on the spacecraft 120E-120F of thebottom-most layer 124C of the stack 122. Additionally, for example, thefirst end 128 can include a plurality of biasing devices 138, whichapply the biasing forces between the first end 128 of the adaptor 126and the bottom-most layer 124C of the stack 122. As described above, thebiasing devices 138 can thus facilitate separating the bottom-most layer124C of the stack 122 from the adaptor 126 responsive to the separationnuts 234 actuating from the first state to the second state.

The second end 130 of the adaptor 126 has a configuration correspondingto the support surface 132 of the launch vehicle 116. As one example,the second end 130 can have a size and/or shape that corresponds to asize and/or shape of a feature on the support surface 132 such as, forexample, a coupling mechanism and/or receptacle on the support surface132 for receiving the second end 130.

In some instances, the support surface 132 of one type of launch vehicle116 may differ from the support surface 132 of another type of launchvehicle 116. To adapt the spacecraft system 112 to a variety ofdifferent launch vehicles 116, a set of adaptors 126 can be providedwith a plurality of different second end 130 configurations, whichrespectively correspond to the support surface 132 of a different typeof launch vehicle 116. As such, the spacecraft system 112 can be readilydeployed using a variety of different types of launch vehicles 116 byselecting, from among the set of adaptors 126, an adaptor 126corresponding to a particular type of launch vehicle 116 to be used fora particular launch of the spacecraft system 112.

As noted above, the spacecraft 120A-120F can include satellites and/orinterplanetary probes. In the example depicted in FIGS. 3-4, thespacecraft 120A-120F include, among other systems and components, one ormore propulsion systems 148, solar panels 150, and/or antennas 152. Thepropulsion systems 148 can move the spacecraft 120A-120F to and/ormaintain the spacecraft 120A-120F in a particular location in orbit. Forexample, the propulsion system 148 can include an electric propulsionmotor (e.g., an ion thruster), a chemical propulsion motor, and/or ahybrid electric/chemical propulsion motor. The solar panels 150 can bepart of a power system configured to power electrical components of thespacecraft 120A-120F. For example, the solar panels 150 can generateelectricity from the sun, and the generated electricity can then be usedto power the spacecraft 120A-120F and/or stored in one or more batteriesfor later use. The antennas 152 can facilitate transmitting and/orreceiving signals for communications between the spacecraft 120A-120Fand another spacecraft and/or a ground station.

In addition to the features shown in FIG. 1, the rocket 110 can includeadditional or alternative features such as, for example, one or morenavigation and/or guidance systems (e.g., a satellite navigation systemand/or an inertial navigation system), and/or stabilization devices(e.g., one or more fins, Vernier engines, gimbals, and/or gyroscopes).

III. Example Operations

In operation, the launch vehicle 116 is launched into orbit. Once inorbit, the fairing 114 can separate from the launch vehicle 116 orotherwise open to expose the spacecraft system 112 to an externalenvironment (e.g., outer space). The controller 136 can then cause thelayers 124A-124C to release, layer by layer, from the stack 122. Forexample, the controller 136 can transmit signals to the releasablefasteners 134A-1341 and, responsive to receiving the signals, thereleasable fasteners 134A-1341 can actuate from the first state to thesecond state to release the layers 124A-124C, layer by layer, from thestack 122.

In an example, the controller 136 can wait for a period of time betweentransmissions of the signals to allow the launch vehicle 116 to travel apredetermined distance between releasing the layers 124A-124C. This canhelp to deploy the spacecraft 120A-120F from the launch vehicle 116 inrelatively close proximity of orbital slots assigned to the spacecraft120A-120F.

For each layer 124A-124C, after the layer 124A-124C releases from thestack 122, one or more of the biasing devices 138A-1381 apply biasingforces to the layer 124A-124C to facilitate separating the layer124A-124C from the stack 122. By applying the biasing forces tofacilitate separating the layer 124A-124C from the stack 122, the riskof collision between the layer 124A-124C and the stack 122 can bereduced or minimized.

Further, as described above, the biasing devices 138A-1381 can cause thelayer 124A-124C released from the stack 122 to rotate as the layer124A-124C separates from the stack 122. Within examples, each layer124A-124C can rotate about an axis that is normal to the sun. Byrotating the layer 124A-124C about an axis that is normal to the sun,the spacecraft 120A-120F of the layer 124A-124C can be more equallyexposed to sun. This can provide a thermally-stable and power-stableconfiguration of the spacecraft 120A-120F in the layer 124A-124C duringseparation from the stack 122.

For each layer 124A-124C, after the layer 124A-124C releases from thestack 122 and/or the adaptor 126, the controller 136 can cause thespacecraft 120A-120F in the layer 124A-124C to release from each other.For example, after each layer 124A-124C releases from the stack 122and/or the adaptor 126, the controller 136 can wait for a period of timeand then transmit a signal to the releasable fastener(s) 134A-1341coupling the spacecraft 120A-120F of the layer 124A-124C. Responsive toreceiving the signals, the releasable fasteners 134A-1341 can actuatefrom the first state to the second state to release spacecraft 120A-120Fof the layer 124A-124C from each other.

When the spacecraft 120A-120F of the layer 124A-124C release from eachother, the biasing device(s) 138G-1381 between the spacecraft 120A-120Fof the layer 124A-124C facilitate separating the spacecraft 120A-120Ffrom each other. As such, the biasing device(s) 138G-1381 can help toreduce or minimize the risk of collision between the spacecraft120A-120F.

In one example, the controller 136 causes the layers 124A-124C torelease, layer by layer, in an order from a top-most layer of the stack122 to a bottom-most layer of the stack 122. FIGS. 6A-61 depict thespacecraft system 112 deploying the spacecraft 120A-120F according to animplementation of this example. FIG. 6A depicts a side view of thespacecraft system 112 according to an example.

To release the first layer 124A from the stack 122, the controller 136actuates the second releasable fastener(s) 134B and the third releasablefastener(s) 134C. FIG. 6B depicts the spacecraft system 112 after thefirst layer 124A releases from the stack 122. As shown in FIG. 6B,responsive to the first layer 124A releasing from the stack 122, thefirst biasing device(s) 138A and the second biasing device(s) 138B applybiasing forces to the first layer 124A to facilitate separating thefirst layer 124A from the stack 122 in a direction indicated by arrow654. The biasing forces applied to the first layer 124A by the firstbiasing device(s) 138A and the second biasing device(s) 138B also causethe first layer 124A to rotate in a direction indicated by arrow 656.

FIG. 6C further illustrates the first spacecraft 120A and the secondspacecraft 120B of the first layer 124A rotating in the directionindicated by the arrow 656. As shown in FIG. 6C, the first layer 124Arotates about an axis 658, which is normal to a direction of the sun.The direction of the sun is indicated by an arrow 660 in FIG. 6C.

After the first layer 124A releases from the stack 122, the controller136 actuates the first releasable fastener(s) 134A to release the firstspacecraft 120A and the second spacecraft 120B from each other, as shownin FIG. 6D. Responsive to the first spacecraft 120A and the secondspacecraft 120B releasing from each other, the seventh biasing device(s)138G apply a biasing force to the first spacecraft 120A and the secondspacecraft 120B to facilitate separating the first spacecraft 120A andthe second spacecraft 120B from each other, as indicated by an arrow 662in FIG. 6D.

After releasing the first layer 124A from the stack 122 and/or releasingthe first and second spacecraft 120A-120B from each other, thecontroller 136 actuates the fifth releasable fastener(s) 134E and thesixth releasable fastener(s) 134F to release the second layer 124B fromthe stack 122. FIG. 6E depicts the spacecraft system 112 after thesecond layer 124B releases from the stack 122. Responsive to the secondlayer 124B releasing from the stack 122, the third biasing device(s)138C and the fourth biasing device(s) 138D apply biasing forces to thesecond layer 124B to facilitate separating the second layer 124B fromthe stack 122 and rotating the second layer 124B about an axis normal tothe sun, as indicated by arrow 664.

After the second layer 124B releases from the stack 122, the controller136 actuates the fourth releasable fastener(s) 134D to release the thirdspacecraft 120C and the fourth spacecraft 120D from each other, as shownin FIG. 6F. Responsive to the third spacecraft 120C and the fourthspacecraft 120D releasing from each other, the eighth biasing device(s)138H apply a biasing force to the third spacecraft 120C and the fourthspacecraft 120D to facilitate separating the third spacecraft 120C andthe fourth spacecraft 120D from each other, as indicated by an arrow 666in FIG. 6F.

After releasing the second layer 124B from the stack 122 and/orreleasing the third and fourth spacecraft 120C-120D from each other, thecontroller 136 actuates the eighth releasable fastener(s) 134H and theninth releasable fastener(s) 1341 to release the third layer 124C fromthe adaptor 126. FIG. 6G depicts the spacecraft system 112 after thethird layer 124C releases from the adaptor 126. Responsive to the thirdlayer 124C releasing from the adaptor 126, the fifth biasing device(s)138E and the sixth biasing device(s) 138F apply biasing forces to thethird layer 124C to facilitate separating the third layer 124C from theadaptor 126 and rotating the third layer 124C about an axis normal tothe sun, as indicated by arrow 668.

After the third layer 124C releases from the adaptor 126, the controller136 actuates the ninth releasable fastener(s) 1341 to release the fifthspacecraft 120E and the sixth spacecraft 120F from each other, as shownin FIG. 6H. Responsive to the fifth spacecraft 120E and the sixthspacecraft 120F releasing from each other, the ninth biasing device(s)1381 apply a biasing force to the fifth spacecraft 120E and the sixthspacecraft 120F to facilitate separating the fifth spacecraft 120E andthe sixth spacecraft 120F from each other, as indicated by an arrow 670in FIG. 6H.

In the example described above and depicted by FIGS. 6A-6H, thecontroller 136 causes the layers 124A-124C to release in an order from atop-most layer 124A to a bottom-most layer 124C. In another example, thecontroller 136 can cause the stack 122 to release from the launchvehicle 116 before the controller 136 causes at least one of the layers124A-124B to release from the stack 122.

For instance, the controller 136 can be configured to determine that afault condition occurred during the release process described above(i.e., releasing in an order from the top-most layer to the bottom-mostlayer). As one example, the controller 136 can determine that a faultcondition occurs when a layer 124A-124C does not release responsive tothe controller 136 transmitting a signal to trigger release of the layer124A-124C. Responsive to the controller 136 determining that the faultcondition occurred, the controller 136 can cause the stack 122 torelease from the adaptor 126 and then cause the layers 124A-124C torelease in an order from the bottom-most layer to the top-most layer. Asdescribed above, after each layer 124A-124C releases from the stack inthis order, the controller 136 causes the spacecraft in the layer124A-124C to release from each other.

As described above, the layers 124A-124C can each rotate about an axisthat is normal to the direction of the sun when released from the stack122 and/or the adaptor 126. In an example, this can be achieved at leastin part by the controller 136 releasing the layer 124A-124C when thelaunch vehicle 116 is oriented such that a longitudinal axis of thespacecraft system 112 is parallel with the direction of the sun.Additionally, in an example, the controller 136 can release the layers124A-124C with the spacecraft system 112 at a trailing end of the launchvehicle 116 relative to a direction of travel of the launch vehicle 116.This can further help reduce the risk of collision between the releasedlayer 124A-124C and the stack 122.

Referring now to FIG. 7, a flow chart for a process 700 of deploying aplurality of spacecraft from a launch vehicle is depicted according toan example embodiment. The plurality of spacecraft are in a stack havingone or more layers, each layer includes at least two spacecraft, andeach spacecraft is releasably coupled to one or more adjacent spacecraftin the stack. As shown in FIG. 7, the process 700 includes releasing,layer by layer, the one or more layers from the stack at block 710. Foreach layer, the process 700 also includes after releasing the layer fromthe stack, releasing the at least two spacecraft of the layer from eachother at block 712.

FIGS. 8-12 depict additional aspects of the process 700 according tofurther examples. As shown in FIG. 8, at block 714, the process 700 caninclude, for each layer, responsive to releasing the layer from thestack at block 712, separating the layer from the stack using aplurality of biasing devices applying a biasing force between the layerand the stack. As shown in FIG. 9, at block 716, the process 700 caninclude, for each layer, rotating the layer about an axis as the layerseparates from the stack. In an example, the axis is normal to the sun.As shown in FIG. 10, to rotate the layer about the axis at block 716,the process 700 can include applying a first biasing force to firstportion of the layer and applying a second biasing force to a secondportion of the layer at step 718. The first biasing force can bedifferent than the second biasing force.

As shown in FIG. 11, at block 720, the process 700 can include,responsive to releasing the at least two spacecraft of the layer fromeach other at block 712, separating the at least two spacecraft fromeach other using a biasing device that applies a biasing force betweenthe at least two adjacent spacecraft. In an example, separating thelayer from the stack at block 712 and separating the at least twospacecraft from each other at block 720 can be performed entirelypassive (e.g., without using thrusters on the spacecraft). As shown inFIG. 12, the process 700 can include, prior to releasing at least one ofthe one or more layers, releasing the stack from the launch vehicle atblock 722.

IV. Example Variations

In the example depicted in FIGS. 2-6H, the spacecraft system 112includes a stack 122 having three layers 124A-124C with two spacecraft120A-120F per layer 124A-124C. As described above, the spacecraft system112 can include greater or fewer layers 124A-124C and/or greater orfewer spacecraft 120A-120F per layer 124A-124C in other examples. Ingeneral, the spacecraft system can include a stack having N layers and Mspacecraft per layer, wherein N and M are both integer values, where Nis greater than or equal to one and M is greater than or equal to two.

Additionally, in the example spacecraft system 112 depicted in FIGS.2-6H, the third spacecraft 120C and the fourth spacecraft 120D are eachcoupled to three adjacent spacecraft 120A-120F. However, in anotherexample, the third 120C and/or the fourth spacecraft 120D can be coupledto two spacecraft 120A-120F or one spacecraft 120A-120F. That is, whileeach spacecraft 120A-120F can be releasably coupled to one or moreadjacent spacecraft 120A-120F, a spacecraft 120A-120F need not becoupled to every adjacent spacecraft 120A-120F in some examples.

Further, as noted above, the biasing devices 138A-1381 can facilitateseparating the layers 124A-124C and/or spacecraft 120A-120F from eachother in a passive manner. In an implementation, for each layer124A-124C, separating the layer 124A-124C from the stack 122 and/orseparating the spacecraft 120A-120F in layer 124A-124C from each othercan be entirely passive. That is, the biasing devices 138A-1381 canfacilitate separating the components without the use of the propulsionsystems 148 on the spacecraft 120A-120F. In another implementation, thespacecraft 120A-120F can additionally or alternatively use thepropulsion systems 148 to facilitate separating the layers 124A-124Cfrom the stack 122 and/or separating the spacecraft 120A-120F from eachother.

Example aspects have been described above. After studying theconfigurations, examples, and arrangements described herein a skilledperson may come to understand, however, that changes and modificationsmay be made without departing from the true scope and spirit of thedisclosure. The description of the different advantageous aspects hasbeen presented for purposes of illustration and description, and is notintended to be exhaustive or limited to the form disclosed. Afterreviewing this disclosure, many modifications and variations will becomeapparent to those of ordinary skill in the art. Further, differentadvantageous aspects may provide different advantages as compared toother advantageous aspects. The example aspects selected are chosen anddescribed in order to explain the principles of the disclosure, thepractical application, and to enable others of ordinary skill in the artto understand the disclosure with various modifications as are suited tothe particular use contemplated.

1. A spacecraft system, comprising: a plurality of spacecraft in anarrangement, wherein the arrangement has one or more layers, each layerincludes at least two spacecraft, and each spacecraft is releasably anddirectly coupled to one or more adjacent spacecraft in the arrangement;a plurality of releasable fasteners, wherein each releasable fastenerreleasably couples a respective one of the plurality of spacecraft to arespective one of the one or more adjacent spacecraft in thearrangement; and a controller configured to perform a set of acts,wherein the set of acts comprise, for each layer: cause the layer torelease from a launch vehicle, and after the layer releases from thelaunch vehicle, cause the at least two spacecraft in the layer torelease from each other.
 2. The spacecraft system of claim 1, furthercomprising an adaptor having a first end coupled to a bottom-most layerof the arrangement, and a second end configured to couple to a launchvehicle.
 3. The spacecraft system of claim 2, further comprising aplurality of biasing devices between at least one of (i) the bottom-mostlayer of the arrangement and the adaptor or (ii) adjacent layers in thearrangement, wherein the plurality of biasing devices apply a biasingforce between the at least one of (i) the bottom-most layer of thearrangement and the adaptor or (ii) the adjacent layers to facilitateseparating each layer from the launch vehicle after the layer releasesfrom the launch vehicle.
 4. The spacecraft system of claim 3, wherein,for each layer of the arrangement, at least one of the plurality ofbiasing devices applies a different biasing force to the layer than atleast another of the plurality of biasing devices such that the layerrotates as the layer separates from the launch vehicle.
 5. Thespacecraft system of claim 3, wherein the plurality of biasing devicescomprises a plurality of springs, and wherein the at least one of theplurality of biasing devices has a characteristic that is different thana characteristic of the at least another of the plurality of biasingdevices, and wherein the characteristic is at least one of a springconstant or a length.
 6. The spacecraft system of claim 1, furthercomprising a plurality of biasing devices between the at least twospacecraft of each layer, wherein the plurality of biasing devices applya biasing force between the at least two spacecraft that facilitatesseparating the at least two spacecraft from each other after the atleast two spacecraft are released from each other.
 7. The spacecraftsystem of claim 1, wherein the controller is configured to: determinethat a fault condition occurred, and responsive to a determination thatthe fault condition occurred, cause the arrangement to release from thelaunch vehicle before the controller causes at least one of the one ormore layers to release from the arrangement.
 8. The spacecraft system ofclaim 1, wherein a quantity of layers of the one or more layers is one.9. The spacecraft system of claim 1, wherein each spacecraft comprises asatellite.
 10. The spacecraft system of claim 1, wherein, for eachlayer, the at least two spacecraft in the layer have substantially thesame height.
 11. The spacecraft system of claim 1, wherein eachreleasable fastener comprises a pyrotechnic charge that is configured tobe activated remotely by the controller to cause the pyrotechnic chargeto break the releasable fastener into a plurality of pieces.
 12. Amethod of dispensing a plurality of spacecraft from a launch vehicle,wherein the plurality of spacecraft are in an arrangement having one ormore layers, each layer includes at least two spacecraft, and eachspacecraft is releasably and directly coupled to one or more adjacentspacecraft in the arrangement by a respective releasable fastener, themethod comprising: releasing, layer by layer, the one or more layersfrom a launch vehicle; and for each layer, after releasing the layerfrom the launch vehicle, releasing the at least two spacecraft of thelayer from each other.
 13. The method of claim 12, further comprising,for each layer, responsive to releasing the layer from the launchvehicle, separating the layer from the launch vehicle using a pluralityof biasing devices applying a biasing force to the layer.
 14. The methodof claim 13, further comprising, for each layer, rotating the layerabout an axis as the layer separates from the launch vehicle.
 15. Themethod of claim 14, wherein rotating the layer about the axis comprisesapplying a first biasing force to first portion of the layer andapplying a second biasing force to a second portion of the layer, andwherein the first biasing force is different than the second biasingforce.
 16. The method of claim 12, further comprising responsive toreleasing the at least two spacecraft of the layer from each other,separating the at least two spacecraft from each other using a biasingdevice that applies a biasing force between the one or more adjacentspacecraft.
 17. The method of claim 12, further comprising prior toreleasing the one or more layers: determining a fault conditionoccurred; and responsive to determining the fault condition occurred,releasing the arrangement from the launch vehicle.
 18. The method ofclaim 17, wherein determining the fault condition occurred comprisesdetermining that a layer of the one or more layers did not releaseresponsive to a controller transmitting a signal to trigger release ofthe layer.
 19. The method of claim 12, wherein a quantity of layers ofthe one or more layers is one.
 20. A non-transitory computer-readablemedium having stored thereon, program instructions that when executed bya controller, cause a spacecraft system to perform a set of acts,wherein the spacecraft system includes a plurality of spacecraft in anarrangement, the arrangement has one or more layers, each layer includesat least two spacecraft, and each spacecraft is releasably and directlycoupled to one or more adjacent spacecraft in the arrangement by arespective releasable fastener, the set of acts comprising: releasing,layer by layer, the one or more layers from a launch vehicle; and foreach layer, after releasing the layer from the launch vehicle, releasingthe at least two spacecraft of the layer from each other.